The comparative effectiveness of glasdegib in combination with low-dose cytarabine versus azacitidine by bone marrow blasts counts among patients with newly-diagnosed acute myeloid leukemia who are ineligible for intensive chemotherapy.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e19512-e19512
Author(s):  
Sophie van Beekhuizen ◽  
Yannan Hu ◽  
Ana Gezin ◽  
Bart Heeg ◽  
Timothy Bell ◽  
...  

e19512 Background: Acute myeloid leukemia (AML) is an orphan disease with one of the lowest five-year survival rates among myeloid malignancies. Recently, a randomized, open label study among previously untreated, chemotherapy-ineligible AML patients demonstrated improved overall survival (OS) among patients treated with glasdegib (GLAS) + LDAC compared with LDAC alone. Two trials of AZA vs. conventional care regimens report data by bone marrow blast (BMB) counts: one with 20-30% and the other with >30%. In the absence of head-to-head comparisons, this study aims to perform the indirect treatment comparison between GLAS+LDAC and AZA by BMB counts. Methods: As there were potential imbalances between the GLAS and AZA trials and within the AZA trial arms in the baseline characteristics (e.g. poor cytogenetics% and de novo%), simulated treatment comparisons (STCs) for GLAS+LDAC vs. LDAC were performed to derive robust estimation by adjusting for the imbalances in the baseline effect modifiers. Afterwards, the classical network meta-analysis (NMA) was conducted. To derive the hazard ratio (HR) of GLAS+LDAC vs. AZA, three NMAs were conducted in each BMB group. Each NMA used a different HR of GLAS+LDAC vs. LDAC: 1) an unadjusted HR (classical NMA), 2) an STC adjusted HR adjusting for potential imbalances between the trials, and 3) an STC adjusted HR additionally accounting for potential imbalances between arms within the AZA trial. Results: In the 20-30% BMB group (N = 30), the OS HRs of GLAS+LDAC vs. AZA resulting from the three respective NMAs were as follows: 1) 0.46 [95% confidence interval: 0.10-2.14], 2) 0.31 [0.06-1.69], and 3) 0.36 [0.06-2.15]. In the > 30% BMB group (N = 80), the HRs were 1) 0.69 [0.39-1.20], 2) 0.48 [0.23-0.97], and 3) 0.48 [0.24-1.00]. All the HRs suggest that patients with GLAS+LDAC have a survival advantage over patients with AZA. Conclusions: Both the classical NMAs and the NMAs based on the STC adjusted HRs correcting for the potential imbalances at baseline suggest that GLAS+LDAC may be preferred over AZA as a treatment option for previously untreated chemotherapy-ineligible AML patients regardless of BMB counts. [Table: see text]

Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1997-2004 ◽  
Author(s):  
G Del Poeta ◽  
R Stasi ◽  
G Aronica ◽  
A Venditti ◽  
MC Cox ◽  
...  

Abstract Cytofluorimetric detection of the multidrug resistance (MDR)-associated membrane protein (P-170) was performed at the time of diagnosis in 158 patients with acute myeloid leukemia using the C219 monoclonal antibody (MoAb). In 108 of these cases the JSB1 MoAb was also tested. An improved histogram subtraction analysis, based on curve fitting and statistical test was applied to distinguish antigen-positive from antigen-negative cells. A marker was considered positive when more than 20% of the cells were stained. At onset, P-170 was detected in 43% of cases with C219 and in 73% of cases with JSB1. There was a strict correlation between C219 and JSB1 positivity, as all C219+ cases were also positive for JSB1 MoAb (P < .001). No relationship was found between sex, age, organomegaly, and MDR phenotype. Significant correlation was found between CD7 and both C219 and JSB1 expression (P < .001 and .001, respectively). C219-negative phenotype was more often associated with a normal karyotype (24 of 55 with P = .030). Rhodamine 123 (Rh123) staining and flow cytometry analysis showed a significantly decreased mean fluorescence in 51 C219+ and 38 JSB1+ patients compared to 42 MDR negative ones (P < .001). The rate of first complete remission (CR) differed both between C219+ and C219- cases and between JSB+ and JSB- ones (30.9% v 71.1% and 35.4% v 93.1%, respectively, P < .001). Of the 21 C219+ patients who had yielded a first CR, 19 (90.4%) relapsed, compared with 28 of 64 (43.7%) C219- patients (P < .001). Of the 28 JSB1+ patients in first CR, 17 (60.7%) relapsed relative to 8 (29.6%) of 27 JSBI- ones (P = .021). A higher rate of relapses among MDR+ compared with MDR- patients was observed both for C219 and JSB1 MoAbs taken separately (C219 80% v 44%; JSB1 52% v 27%), with no relationship to age. The survival rates (Kaplan-Meyer method) were significantly shorter both in C219+ patients and in JSB1+ cases (P < .001). Disease-free survival curves followed this same trend. The combination (C219- JSB1+) identified a subset of patients with an intermediate outcome compared to C219 positive cases. The prognostic value of both markers (C219 and JSB1) was confirmed in multivariate analysis. These results suggest that the assessment of MDR phenotype by flow cytometry may be an important predictor of treatment outcome.


PLoS ONE ◽  
2014 ◽  
Vol 9 (6) ◽  
pp. e93353 ◽  
Author(s):  
Ruxiu Tie ◽  
Tiansong Zhang ◽  
Huarui Fu ◽  
Limengmeng Wang ◽  
Yebo Wang ◽  
...  

Blood ◽  
2001 ◽  
Vol 97 (11) ◽  
pp. 3605-3611 ◽  
Author(s):  
Marry M. van den Heuvel-Eibrink ◽  
Erik A. C. Wiemer ◽  
Marjan J. de Boevere ◽  
Bronno van der Holt ◽  
Paula J. M. Vossebeld ◽  
...  

The expression of P-glycoprotein (P-gp), encoded by theMDR1 gene, is an independent adverse prognostic factor for response and survival in de novo acute myeloid leukemia (AML). Little is known about MDR1 expression during the development of disease. The present study investigated whether MDR1 gene– related clonal selection occurs in the development from diagnosis to relapsed AML, using a genetic polymorphism of the MDR1 gene at position 2677. Expression and function of P-gp were studied using monoclonal antibodies MRK16 and UIC2 and the Rhodamine 123 retention assay with or without PSC 833. No difference was found in the levels of P-gp function and expression between diagnosis and relapse in purified paired blast samples from 30 patients with AML. Thirteen patients were homozygous for the genetic polymorphism ofMDR1 (n = 7 for guanine, n = 6 for thymidine), whereas 17 patients were heterozygous (GT). In the heterozygous patients, no selective loss of one allele was observed at relapse. Homozygosity for the MDR1 gene (GG or TT) was associated with shorter relapse-free intervals (P = .002) and poor survival rates (P = .02), compared with heterozygous patients. No difference was found in P-gp expression or function in patients with AML with either of the allelic variants of the MDR1 gene. It was concluded that P-gp function or expression is not upregulated at relapse/refractory disease and expression of one of the allelic variants is not associated with altered P-gp expression or function in AML, consistent with the fact that MDR1 gene–related clonal selection does not occur when AML evolves to recurrent disease.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1073-1073
Author(s):  
Hiroto Inaba ◽  
Jeffrey E Rubnitz ◽  
Elaine Coustan-Smith ◽  
Lie Li ◽  
Brian D Furmanski ◽  
...  

Abstract Abstract 1073 Background: Aberrant receptor tyrosine kinase (RTK) signaling arising from genetic abnormalities, such as FLT3-internal tandem duplications (FLT3-ITD), is an important mechanism in the development and growth of acute myeloid leukemia (AML) and is often associated with a poor outcome. Hence, inhibition of RTK signaling is an attractive novel treatment option, particularly for disease that is resistant to conventional chemotherapy. We evaluated the clinical activity of the multikinase inhibitor sorafenib in children with de novo FLT3-ITD–positive AML or relapsed/refractory AML. Methods: Fourteen patients were treated. Six patients with newly diagnosed FLT3- ITD–positive AML (aged 9–16 years; median, 12 years) received 2 cycles of remission induction therapy and then started sorafenib (200 mg/m2 twice daily for 20 days) the day after completing induction II (low-dose cytarabine, daunorubicin, and etoposide). Nine patients (aged 6–17 years; median, 9 years) with relapsed AML (including one treated on the above regimen) received sorafenib alone (2 dose levels; 200 and 150 mg/m2) twice daily for the first week of therapy, concurrently with clofarabine and cytarabine on days 8–12, and then alone from days 13 to 28. Sorafenib pharmacokinetics were analyzed at steady-state on day 8 of sorafenib in patients with newly diagnosed AML and on day 7 in patients with relapsed AML. In patients with relapsed AML, the effect of sorafenib on signaling pathways in AML cells was assessed by flow cytometry. Results: All 6 newly diagnosed patients, including 2 whose AML was refractory to induction I, achieved a complete remission (CR) after induction II; 5 had negative minimal residual disease (MRD; <0.1% AML cells in bone marrow) after induction II. Both patients in this group who relapsed achieved second remissions, one with sorafenib alone and one on the relapse regimen described above. Of the 9 patients with relapsed AML, 6 (4 with FLT3-ITD) were treated with sorafenib 200 mg/m2. All 6 had a >50% decrease in blast percentage and/or bone marrow cellularity after 1 week of sorafenib. After concurrent sorafenib and chemotherapy, 5 of the 9 patients with relapsed AML achieved CR (2 had negative MRD) and 2 achieved a partial remission (PR; 5%-25% AML cells in bone marrow); all 4 patients with FLT3-ITD had a CR or PR. After sorafenib treatment, 6 patients underwent HSCT while 2 with FLT3-ITD who could not receive HSCT were treated with single-agent sorafenib and have maintained CR for up to 8 months. Hand-foot skin reaction (HFSR) or rash occurred in all patients and improved with cessation of sorafenib. Dose-limiting toxicity (DLT, grade 3 HFSR and/or rash) was observed in 3 of the 6 patients with relapsed AML treated with 200 mg/m2 of sorafenib; no DLT was observed at 150 mg/m2. The effect of sorafenib on downstream RTK signaling was tested in the leukemic cells of 4 patients: in most samples, phosphorylation of S6 ribosomal protein and 4E-BP1 was inhibited. The mean (± SD) steady-state concentration (Css) of sorafenib was 3.3 ± 1.2 mg/L in the newly diagnosed group and 6.5 ± 3.6 mg/L (200 mg/m2) and 7.3 ± 3.6 mg/L (150 mg/m2) in those with relapsed AML. In both groups, the mean conversion of sorafenib to sorafenib N-oxide was 27%-35% (approximately 3 times greater than previously reported), and mean sorafenib N-oxide Css was 1.0–3.2 mg/L (2.1-6.7 μM). In a 442-kinase screen, the inhibitory profiles of sorafenib N-oxide and sorafenib were similar, and FLT3-ITD phosphorylation was potently inhibited by both forms (sorafenib N-oxide Kd = 0.070 μM; sorafenib Kd = 0.094 μM). Sorafenib N-oxide inhibited the growth of an AML cell line with FLT3-ITD (IC50 = 0.026 μM) and 4 AML cell lines with wild-type FLT3 (IC50 = 3.9–13.3 μM) at approximately half the potency of sorafenib. Conclusion: In children with de novo FLT3-ITD and relapsed/refractory AML, sorafenib given alone or with chemotherapy induced dramatic responses and inhibited aberrant RTK signaling in leukemic cells. Sorafenib and its active metabolite (sorafenib N-oxide) likely contribute to both efficacy and toxicity. These results warrant the incorporation of sorafenib into future pediatric AML trials. Disclosures: Inaba: Bayer/Onyx: Research Funding. Off Label Use: Sorafenib and clofarabine: both used for treatment of pediatric acute myeloid leukemia.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2697-2697
Author(s):  
Weng-Chi Lei ◽  
Wen-Chien Chou ◽  
Bor-Shen Ko ◽  
Hsin-An Hou ◽  
Hwei-Fang Tien

Abstract Abstract 2697 Purpose: Although the clinical and biological features of Isocitrate dehydrogenase (IDH) mutations in acute myeloid leukemia (AML) have been characterized, its stability and in vivo sufficiency of the mutation alone for leukemogenesis remain uninvestigated. Patients and Methods: Mutations of IDH and other clinically relevant genes were analyzed in the bone marrow from 446 adult patients with de novo non-M3 AML. IDH2 mutations were examined serially in 140 patients at diagnosis and after chemotherapy. Results: Among the 446 adults with de novo non-M3 AML, IDH2 R172, R140, and IDH1 R132 mutations occurred at a frequency of 2.9%, 9.2%, and 6.1%, respectively. IDH2 mutation was associated with higher platelet counts (p=0.046), intermediate-risk (p=0.002) or normal karyotype (p=0.023), and isolated +8 (p=0.014), but was inversely correlated with expression of HLA-DR (p=0.002), CD34 (p=0.039), CD15 (p=0.003), CD7 (p=0.010), and CD56 (p=0.048), and was mutually exclusive with WT1 mutation (p=0.037) and core-binding factor translocations (p=0.001). All these correlations became stronger when IDH1 and IDH2 mutations were considered together, suggesting similarity of biological roles between these 2 mutations. However, IDH2 but not IDH1 mutation conferred a better prognosis (Fig 1), especially in those with normal karyotype or intermediate cytogenetics (median overall survival: not reached vs. 58 months, p=0.044 and not reached vs. 19 months, p=0.027 for normal and intermediate karyotype group, respectively). Importantly, IDH2 but not IDH1 mutation was an independent favorable prognostic factor (HR: 0.332, 95% CI: 0.159–0.694; p=0.003). Patients with IDH2−/FLT3-ITD+ genotype had especially worse prognosis (median OS of IDH2−/FLT3-ITD+ vs. IDH2+/FLT3-ITD− group: 12 months vs. not reached; p=0.003; median OS of IDH2−/FLT3-ITD+ vs. IDH2+/FLT3-ITD+ or IDH2−/FLT3-ITD− group : 12 months vs. 35 months; p<.0001) (Fig 2A). The worse prognosis was also seen in patients with IDH−/FLT3-ITD+ genotype (Fig 2B). Serial analyses of IDH2 mutations during the clinical course of 140 patients confirmed the stability of this mutation; all the patients with IDH2 mutations at diagnosis harbored the same mutation at relapse with the exception of one patient who had extramedullary but not bone marrow relapse, while none of the IDH2-wild patients acquired this mutation at relapse. Importantly, sequential samples from two patients in long-term remission retained the original R140Q mutation while other accompanied mutations, FLT3-ITD in the first patient and NPM1 in the second, respectively, disappeared. In the first patient, the skin tissue was absent of the mutation and in the second, the mutation was restricted in myeloid cells but spared in lymphocytes indicating the mutation was acquired in these two patients. Conclusion: IDH2 mutation is a stable marker during disease evolution and confers favorable prognosis. FLT3-ITD combined with wild type IDH2 exerted synergistic negative impact on survival. IDH2 mutation alone is insufficient for leukemogenesis. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2544-2544
Author(s):  
Xiuli Wang ◽  
Haiping Dai ◽  
Qian WANG ◽  
Qinrong Wang ◽  
Yang Xu ◽  
...  

Abstract Abstract 2544 Somatic mutation of the EZH2 gene is seen in myelodisplastic syndrome, myelofibrosis, and chronic myelomonocytic leukemia patients. The prevalence and prognostic impact of somatic mutations of EZH2 in patients with acute myelogenous leukemia (AML) remains unknown. In this study, we sought to determine the incidence and clinical implications of somatic EZH2 mutations in 714 patients with de novo AML by PCR amplification of the entire coding region followed by direct bidirectional DNA sequencing. EZH2 mutations were identified in 13/714 (1.8%) of AML patients and occurred almost exclusively in males (11/13, P=0.033). In univariate analysis, the presence of EZH2 mutations was significantly associated with lower blast percentage (21–30%) in bone marrow (P=0.0001) and −7/del(7q) (P=0.025). There was no difference in the incidence of mutations in 13 genes, including ASXL1, CBL, c-KIT, DNMT3A, FLT3, IDH1, IDH2, MLL, NPM1, NRAS, RUNX1, TET2, and WT1, between patients with and without EZH2 mutations. Complete remission, event-free survival or overall survival was similar between AML patients with and without EZH2 mutation (p>0.05). These results demonstrated EZH2 mutation as a recurrent genetic abnormality associated with lower blast percentage in BM and −7/del(7q) in de novo acute myeloid leukemia. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3427-3427
Author(s):  
Michael H Kramer ◽  
Qiang Zhang ◽  
Robert W. Sprung ◽  
Petra Erdmann-Gilmore ◽  
Daniel R George ◽  
...  

Abstract Introduction: Proteins, despite being the primary effectors of cellular processes, are often studied only indirectly through analysis of the transcriptome. However, it is clear that the relationship between mRNA expression and protein expression is approximate at best. In Acute Myeloid Leukemia (AML), the genome and transcriptome have been thoroughly characterized, but the proteome has been less well studied. Here, we present a deep-scale study of the proteomes of 44 primary AML bone marrow samples representing a wide range of AML across the spectrum of cytogenetic risk, common mutations, and driver fusions. Methods: Bone marrow samples were collected at presentation from 44 adult patients with de novo AML as part of an institutional banking protocol, and buffy coat cells were immediately cryopreserved without further manipulation. Cryovials were thawed in the presence of the cell permeable serine protease inhibitor diisopropyl fluorophosphate (DFP) to inactivate the abundant neutrophil serine proteases (ELANE, CTSG, PRTN3, and PRSS57), and further processed for nano-liquid chromatography mass spectrometry in the presence of an extensive cocktail of protease inhibitors. Both label-free quantification (LFQ) and tandem-mass-tag (TMT) deep-scale proteomics were performed on these 44 patient samples, as well as 3 lineage-depleted bone marrow samples from healthy adult donors. Matching RNA-seq and exome sequencing data were available for the same samples as part of The Cancer Genome Atlas (TCGA) AML project. Results: 10,651 and 6,679 unique proteins were detected in the TMT and LFQ experiments, respectively. Correlations between measurements derived from the independent proteomic platforms (i.e. TMT and LFQ) is higher (mean Spearman correlation, 0.60, Figure 1A) than correlation between proteomic (TMT) and transcriptomic measurements from bulk RNA-seq data (Spearman 0.43, Figure 1B). Quality checks of the proteomic data strongly supported the reliability of quantification of protein measurements; for example, the mean ratio of beta globin protein (HBB) to alpha globin (HBA1) was 1.2 +/- 0.25 (Figure 1C), and several proteins known to be dysregulated by specific AML-initiating fusion proteins (for PML-RARA, HGF and RARA; for RUNX1-RUNX1T1, RUNX1T1; and for CBFB-MYH11, MYH11) were detected in the expected samples (Figure 1D). Globally, 1,364 proteins were differentially expressed in the AML samples (corrected p-value &lt;0.05, fold change ≥ 1.5) compared to the lineage-depleted, healthy bone marrow samples. Globally overexpressed proteins were enriched for ribosomal RNA modification, mitochondrial protein import, nuclear export, and the mitochondrial electron transport chain, among others. These overexpressed proteins include 61 cell surface proteins that could potentially represent therapeutic targets (overexpressed on average in 82% of AML samples, range 25-97%). Globally downregulated proteins in AML samples were enriched for glycogen metabolism and protein groups associated with mature neutrophils (reflecting the expected maturation block in AML), among others. 771 of the 1364 differentially expressed proteins (56.5%) showed only minimal variability in mRNA expression levels (fold change of &lt;1.1 between AML and normal marrow CD34 cell mRNA) that could not explain dysregulated protein expression. Several protein complexes likewise showed coordinated differential expression in the proteomic data, but no change in the transcriptome, including the THO complex (Figure 1E) and the phosphorylase kinase complex (Figure 1F), among others, indicating the presence of posttranscriptional regulation of the levels of many proteins in AML samples. Conclusion: We have created a deep-scale proteomic database from a set of well-characterized AML samples, allowing for a proteogenomic study of AML. We have identified many examples of post-transcriptional regulation of key metabolic pathways that may be relevant for better understanding AML cell metabolism and therapeutic vulnerabilities. Additional studies linking patterns of protein dysregulation with a variety of AML covariates are underway. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 984-984
Author(s):  
Hui-Jen Tsai ◽  
Ming-Chung Wang ◽  
Sheng-Fung Lin ◽  
Ya-Ping Chen ◽  
Hui-Hwa Hsiao ◽  
...  

Abstract Background: Deprivation of circulating L-asparagine by L-asparaginase, which can lead to the inhibition of RNA and DNA synthesis and subsequent apoptosis of blastic cell, has been implemented as part of multidrug chemotherapy for acute lymphoblastic leukemia since decades ago. Arginine, a semi-essential amino acid in human, is involved in diverse aspects of tumor metabolism and plays critical role for the growth of human cancers. Deficiency of argininosuccinate synthase (ASS), the rate-limiting enzyme for endogenous arginine production in urea cycle, has been found in various cancer tissues. In preclinical studies, pegylated arginine deiminase (ADI-PEG20), which can rapidly convert arginine into citrulline and serve as an arginine depriving agent, was shown to exert in vitro and in vivo anti-proliferative effect on ASS-deficient cancers, such as hepatocellular carcinoma, melanoma, small cell lung cancer, lymphoma and acute myeloid leukemia (AML). The efficacy of ADI-PEG20 is currently under evaluation for various solid tumors in clinical trial setting, including a global phase III trial for hepatocellular carcinoma. Absence of ASS expression has been noted in 87% (46/53) of bone marrow biopsy samples of patients with AML.1 In xenograft model, ADI-PEG20 could reduce the leukemic burden in mice transplanted with primary AML cells.2Herein, we reported the preliminary result of a phase II trial evaluating the therapeutic efficacy of ADI-PEG20 in relapsed/refractory and/or elderly AML patients. Patients and Methods: Patients ≥ 18 years with ASS deficient (by western blotting of bone marrow leukemia cells and/or immunohistochemical staining of bone marrow biopsy), relapsed/refractory or poor-risk AML were eligible. The poor-risk AML includes treatment-related AML, antecedent hematologic disease, unfavorable cytogenetics and de novo AML ≥ 70 years of age. Patients received ADI-PEG20 at 320IU/m2IM weekly (4 weeks as one cycle). Bone marrow aspiration was performed at the time of enrollment, and after the first and second cycle of treatment to evaluate the response. Treatment was continued for each patient until the occurrence of disease progression, development of unacceptable toxicity, death, or withdrawal of consent for any reason. If patients achieved complete remission (CR) or CR with incomplete blood count recovery, the treatment was finished after another 4 cycles of ADI-PEG20. Results: Between October 2013 and May 2014, 9 patients were enrolled, with a male/female ratio of 5/4 and a median age of 62 years (ranged 27 to 79 years old). They were all de novo AML except for 1 with blast-transformed chronic myelomonocytic leukemia. All patients received at least one prior treatment regimen, except for two treatment-naïve elderly patients. After a mean 1.5 cycles of ADI-PEG20 treatment, 2 of 8 evaluable patients achieved CR after 3 and 1 cycles of ADI-PEG20, respectively, while 6 patients had disease progression after an average of 1 cycle of treatment. One patient was not evaluable for response due to withdrawal of consent after the first 2 doses of treatment. Two patients, who died within 2 weeks after the first dose of ADI-PEG20, were considered to have progressive disease. Of the 2 CR patients, 1 was 79 years old with chemo-naïve acute megakaryocytic leukemia (M7) and the other was 69 years old with low-dose Ara-C refractory M2. The most common treatment-related severe adverse events (AE) included grade 4 tumor lysis syndrome, grade 4 infection and treatment-related grade 4 neutropenia occurring in one patient each. The episode of grade 4 neutropenia occurred in the ADI-PEG20 responsive M7 patient. Minor AE included grade 1 hyperuricemia and skin rash in 2 and 1 patients, respectively. Conclusions: ADI-PEG20 is an effective treatment for some patients with ASS-deficient AML with minimal toxicities. Further investigation with genetic and epigenetic profiling to identify patients who will benefit from arginine deprivation therapy is warranted. References. Szlosarek P, et al. Pegylated arginine deiminase (ADI-PEG 20) as a potential novel therapy for argininosuccinate synthetase-deficient acute myeloid leukemia. (AACR Abstract # 467, 2012). 2. Miraki-Moud F, et al. Arginine deprivation with pegylated arginine deiminase induces death of acute myeloid leukaemia cells in vivo. Blood 2012 122:1458. Disclosures Tsai: TWD Pharmaceuticals, Inc: Honoraria.


Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1997-2004 ◽  
Author(s):  
G Del Poeta ◽  
R Stasi ◽  
G Aronica ◽  
A Venditti ◽  
MC Cox ◽  
...  

Cytofluorimetric detection of the multidrug resistance (MDR)-associated membrane protein (P-170) was performed at the time of diagnosis in 158 patients with acute myeloid leukemia using the C219 monoclonal antibody (MoAb). In 108 of these cases the JSB1 MoAb was also tested. An improved histogram subtraction analysis, based on curve fitting and statistical test was applied to distinguish antigen-positive from antigen-negative cells. A marker was considered positive when more than 20% of the cells were stained. At onset, P-170 was detected in 43% of cases with C219 and in 73% of cases with JSB1. There was a strict correlation between C219 and JSB1 positivity, as all C219+ cases were also positive for JSB1 MoAb (P < .001). No relationship was found between sex, age, organomegaly, and MDR phenotype. Significant correlation was found between CD7 and both C219 and JSB1 expression (P < .001 and .001, respectively). C219-negative phenotype was more often associated with a normal karyotype (24 of 55 with P = .030). Rhodamine 123 (Rh123) staining and flow cytometry analysis showed a significantly decreased mean fluorescence in 51 C219+ and 38 JSB1+ patients compared to 42 MDR negative ones (P < .001). The rate of first complete remission (CR) differed both between C219+ and C219- cases and between JSB+ and JSB- ones (30.9% v 71.1% and 35.4% v 93.1%, respectively, P < .001). Of the 21 C219+ patients who had yielded a first CR, 19 (90.4%) relapsed, compared with 28 of 64 (43.7%) C219- patients (P < .001). Of the 28 JSB1+ patients in first CR, 17 (60.7%) relapsed relative to 8 (29.6%) of 27 JSBI- ones (P = .021). A higher rate of relapses among MDR+ compared with MDR- patients was observed both for C219 and JSB1 MoAbs taken separately (C219 80% v 44%; JSB1 52% v 27%), with no relationship to age. The survival rates (Kaplan-Meyer method) were significantly shorter both in C219+ patients and in JSB1+ cases (P < .001). Disease-free survival curves followed this same trend. The combination (C219- JSB1+) identified a subset of patients with an intermediate outcome compared to C219 positive cases. The prognostic value of both markers (C219 and JSB1) was confirmed in multivariate analysis. These results suggest that the assessment of MDR phenotype by flow cytometry may be an important predictor of treatment outcome.


Sign in / Sign up

Export Citation Format

Share Document